Houston we have problem

[Papewaio]

Vuk I have to agree with you.

Humans have been shaping the local environments for thousands of years. When the Australian Aborogines came to Australia he local mega fauna soon died out, the burning of the rain forests changed the local environment to being dominated by gum trees which flourish in burn offs.

New Zealand has on local scales filled in entire valleys with slurry, changed where rivers flow (there was more steam boats dredging NZ rivers for gold then there was steamboats on the Mississippi), in the search for gold they created locally the worlds largest man made desert. Later they modified land into the worlds largest non native pine plantations.

As a undergrad I stood beside the mile deep Kalgoolie mine. I've stood on a mine site in equatorial Borneo and seen how a river was redirected from one side of a mountain to the other so that the gold could be mined underneath the old river bed. I spent my 26th birthday in Mount Newman which they are mining for iron ore will become a local lake when the mining is finished.

Australian land is becoming useless as salt rises in the soil due to local clear felling of all the forest. Localised replanting of scrub and larger trees is required to reverse the salty water table rising.

One farmer proved that by planting trees on his dusty land that it is now a lush green farm with a lake and wetlands. So local change is possible and can be planned.

I agree that we have and continue to impact our local environment.

I also agree that we can affect our weather patterns and the content of our atmosphere. Most of it so far has been accidental but even from the time of the Romans you can look at ice samples in Mont Blanc and verify which minesite the lead was mined in by the isotope ratio. For more recent leaded gas we can trace the lead to the country of origin based on the isotopic ratio in the lead just like a fingerprint. We can see in ice core samples from around the world lead from gas and we can tell if it is from Europe, US or other refineries. We can see the amount of lead peak and diminish as the supply of leaded fuel diminishes.

Likewise for ozone in the atmosphere we can see the amount increase as the various CFC bans took place, there is a much longer tail on this due to the time it takes and other chemicals that are also depleting Ozone.

What I believe is that if we align up enough local environmental changes we have global change.